new species, p. 48). Boulenger GA (1893). Catalogue of the Snakes in the British Museum (Natural History). Volume I., Containing the Families ... Colubridæ Aglyphæ, part. London: Trustees of the British Museum (Natural History). (Taylor and Francis, printers). xiii + 448 pp. + Plates I-XXVIII. (Tropidonotus clarkii, p. 238). Conant, Roger; Bridges, William (1939). What Snake Is That?: A Field Guide to the Snakes of the United States East of the Rocky Mountains. (With 108 drawings by Edmond Malnate). New York and London: D. Appleton-Century Company. Frontispiece map + viii + 163 pp. + Plates A-c, 1-32. (Natrix sipedon clarkii, pp. 105–106 + Plate 20, Figure 57). Cope ED (1895). "On some new North American Snakes". American Naturalist 29: 676-680. (Natrix compressicauda tæniata, new subspecies, pp. 676–677). Kennicott R (1860). "Descriptions of New Species of North American Serpents in the Museum of the Smithsonian Institution, Washington". Proceedings of the Academy of Natural Sciences of Philadelphia 12: 328-338. (Nerodia compressicauda, new species, pp. 335–336). Powell R, Conant R, Collins JT (2016). Peterson Field Guide to Reptiles and Amphibians of Eastern and Central North America, Fourth Edition. Boston and New York: Houghton Mifflin Harcourt. xiv + 494 pp., 47 Plates, 207 Figures. . (Nerodia clarkii, pp. 414–415 + Plate 40). More external links clarkii Reptiles described in 1853 Reptiles of the United States Taxa named by Spencer Fullerton Baird Taxa named by Charles Frédéric Girard